You were close.

# Create an anonymous arrayref
my $arrayref = [1,2,3];

# Create a reference to an existing array
my @array = (1,2,3);
my $arrayref2 = \@array;

# Get a single value from the arrayref:
my $one = $arrayref2->[0];

# Get all the values from the arrayref:
my ($one,$two,$three) = @$arrayref2;
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In the code you posted you wrote:

[$sql_return]
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Which is putting the arrayref provided by DBI inside another arrayref. Instead do this:

@$sql_return
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It might help you visualize the data structure if you use Data::Dumper, like this:

use Data::Dumper;
#...
my $sql_return = $sth_tss->fetchall_arrayref;
print Dumper $sql_return;
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